Modular pallet jack

ABSTRACT

A lift for a fork tine assembly includes a generally upright frame having at least one handle grip portion at a rearward portion thereof. The handle grip portion is fixed relative to the frame. A lift mechanism is secured to the frame. The lift mechanism is capable of attaching to and raising and lowering at least one fork tine. A plurality of wheels support the frame. The at least one fork tine may be part of a first fork tine assembly that can be selectively removed from the lift and replaced with a different configuration fork tine assembly. An optional shelf is provided on the frame for convenience but may be pivoted out of the way when not in use.

BACKGROUND

Pallet lifts or pallet jacks are used to move pallets loaded with goodsaround a warehouse, store and/or in and out of trucks. Larger lifts canbe used to move more pallets at one time; however, sometimes the largerlifts are too wide to be used in some applications. Some pallet jackshave long handles that pivot from a bottom rear edge of the base of thejack. The long handle can also make maneuvering in tight spaces moredifficult.

SUMMARY

A lift for a fork tine assembly includes a generally upright framehaving at least one handle grip portion at a rearward portion thereof.The handle grip portion is fixed relative to the frame. A lift mechanismis secured to the frame. The lift mechanism is capable of attaching toand raising and lowering at least one fork tine. A plurality of wheelssupport the frame. The at least one fork tine may be part of a firstfork tine assembly that can be selectively removed from the lift andreplaced with a different configuration fork tine assembly. An optionalshelf is provided on the frame for convenience but may be pivoted out ofthe way when not in use.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a pallet jack assembly and a pluralityof alternate fork tine assemblies for use in the pallet jack assembly.

FIG. 2 is a perspective view of the lift of FIG. 1.

FIG. 3 is a rear perspective view of the lift assembly and one alternatefork tine assembly of FIG. 1.

FIG. 4 is a bottom perspective view of the lift assembly and fork tineassembly of FIG. 3.

FIG. 5 shows two of the alternate fork tine assemblies plus two morefork tine assemblies that could be connected to the lift of FIG. 2.

FIG. 6 is a side view of the pallet jack assembly of FIG. 1.

FIG. 7 illustrates a pallet jack or lift assembly according to anotherembodiment.

FIG. 8 illustrates the pallet jack of FIG. 7 with the shelf in the firstdeployed position.

FIG. 9 is an enlarged view of the upper portion of the frame of thepallet jack of FIG. 7.

FIG. 10 shows the upper portion of the frame with the shelf lifted tothe unlocked position.

FIG. 11 shows the upper portion of the frame of FIG. 10 with the shelfin a second deployed position.

FIG. 12 shows the upper portion of the frame of FIG. 10 with the shelfin a first deployed position.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A modular pallet jack or lift assembly 10 generally includes a lift 12and a fork tine assembly 14. The lift 12 includes a frame 16 withupright handles 18. Other handle arrangements could also be used, butthe upright handles 18 shown reduce the footprint of the lift assembly10 and increase the maneuverability of the lift assembly 10 in tightspaces.

An actuator lever 20 proximate one of the handles 18 permits theoperator to activate the lift 12. Wheels 22 are mounted below the frame16.

The fork tine assembly 14 includes a support structure 24 having aconnection beam 26 projecting rearward therefrom. The support structure24 connects to the fork tines 28. The tines 28 are supported by pivotingwheels 30 (as is known). The tines 28 may have upper and lower portionsconnected in a known linkage arrangement. The lift 12 selectively liftsthe connection beam 26, thereby lifting the upper portions of the tines28 relative to lower portions of the tines 28 and causing the wheels 30to pivot downward. The fork tine assembly 14 is also connected by bolts34 to lower ends of the frame 16 of the lift 12.

The modular lift assembly 10 permits the lift 12 to be connected withany of a plurality of fork tine assemblies 14, 14 a, 14 b, as shown inFIG. 1. The fork tine assemblies 14, 14 a, 14 b in FIG. 1 each have adifferent spacing between the fork tines 28, 28 a, 28 b. Other differentfeatures could be provided by the alternate assemblies. Thus, the forktine assemblies 14, 14 a, 14 b can be disconnected and swapped withanother one of the fork tine assemblies, 14, 14 a, 14 b and laterreconnected, as needed. This saves the cost of having to purchasemultiple lift assemblies.

FIG. 2 shows the lift 12. The lift 12 houses the lift mechanism 32, suchas hydraulic, electric, etc, lift mechanism 32. Panels on the frame 16shield the lift mechanism 32 from view for an improved appearance andproviding large surfaces for labeling or branding. An opening at thefront of the lift 12 receives the connection beams 26, 26 a, 26 b of thefork tine assemblies 14, 14 a, 14 b. A pair of bolt eyelets 36 at thebase 38 of the frame 16 are configured to receive the bolts 34 (FIG. 1)for connecting the fork tine assemblies 14, 14 a, 14 b. A pair ofgenerally vertical support members 40 extend upward from rear corners ofthe base 38. The handles 18 are formed on portions of the generallyvertical support members 40. An upper portion 42 of the frame 16 definesan upper edge of the lift 12.

FIG. 3 is a rear perspective view of the lift assembly 10 and fork tineassembly 14 a of FIG. 1. The connection beam 26 is received on the liftmechanism 32. A pair of L-brackets 44 are pivotably connected at one endto the bolt eyelets 36 by bolts 34. The L-brackets 44 are each pivotablyconnected at their junction to the respective tine 28, and at theopposite end to a push rod 46 extending below the tine 28.

FIG. 4 is a bottom perspective view of the lift assembly 10 and forktine assembly 14 a of FIG. 3. As is known, the push rods 46 extend beloweach tine 28 to linkage adjacent the wheel 30. In use, when the actuatorlever 20 is activated, the lift mechanism 32 lifts the connection beam26. This raises the tines 28 and the junctions of the L-brackets 44upward toward a position level with the base 38. This causes theL-brackets 44 to rotate, thereby driving push rods 46 forward toward thelinkage of the wheels 30, pivoting wheels 30 downward and rearward. Thetines 28 remain level as they are raised. As can be seen in FIG. 4, theconnection beam 26 a has a projection 48 a projecting downward from theconnection beam 26 a. In this example, the projection 48 a iscylindrical. The other connection beams 26, 26 b, 26 c, 26 d are thesame in this regard. The projection 48 a is received in a socket (FIG.2) at an upper end of the lift mechanism 32. Other connection mechanismscould be used.

FIG. 5 shows two of the alternate fork tine assemblies 14 a, 14 b, plustwo more fork tine assemblies 14 c, 14 d that could be connected to thelift 12 of FIG. 2. As shown, the alternate fork tine assemblies can varyin tine spacing, number of tines, and wheel structure.

FIG. 6 is a side view of the pallet jack assembly 10 of FIG. 1. Again,the pair of bolt eyelets 36 at the base 38 of the frame 16 receive thebolts 34 for connecting the fork tine assembly 14. The generallyvertical support members 40 extend upward from rear corners of the base38. The handles 18 are formed on portions of the generally verticalsupport members 40. The actuator lever 20 is proximate one of thehandles 18. The handles 18 are generally vertical and generally eitherwithin the footprint of the base 38 of the frame 16 or at least do notextend rearward of the frame 16 more than approximately 50% of the depth(front to back) of the base 38 of the frame 16. This is significantlyless than the pallet jacks with long pivoting handles connected atrearward bottom portions of the frame, thus increasing themaneuverability of the pallet jack assembly 10.

FIG. 7 illustrates a pallet jack or lift assembly 110 according toanother embodiment having a deployable and stowable shelf 122. The shelf122 could also be mounted to the pallet jack assembly 10 of FIGS. 1-6.The lift assembly 110 generally includes a lift 112 and a fork tineassembly 114. The lift 112 includes a frame 116 and an upper portion 118extending upward from the frame 116. The frame 116 is located adjacentthe fork tine assembly 114.

At least one vertically extending reinforcement member 120 extends fromthe frame portion 116 and at least partially through the upper portion118. The upper portion 118 includes a shelf 122 that is movable betweena stowed position (FIG. 7) and a deployed position (FIG. 8). The shelf122 is surrounded by a pair of the vertically extending reinforcementmembers 120 and a pair of generally horizontal reinforcement members124. The shelf 122 is made up of a U-shaped member 126 and multiplecross members 128 extending across the U-shaped member 126. However,other configurations for the shelf 122 would be applicable to thisdisclosure.

The shelf 122 is pivotably attached to the upper portion 118 by hinges130. The hinges 130 secure the shelf 122 in the vertical stowed positionand allow the shelf 122 to move to the deployed position. As shown inFIG. 9, the hinges 130 include a pair of arms 132 extending upward fromthe lower one of the generally horizontal reinforcement members 124 andan axle 134 extending between adjacent pairs of arms 134. Distal ends ofthe U-shaped member 126 include elongated slots 131 (FIGS. 11-12).Alternatively, the distal ends of the U-shaped member 126 could includethe axle and the pair of arms 134 could include the slots.

The shelf 122 is moved from the stowed position to the deployed positionby lifting up on the shelf 122 as shown in FIG. 4 which is allowed bythe axle 134 moving through the slots 131 on the U-shaped member 126.The shelf 122 can then be pivoted forward (FIG. 11) or aft (FIG. 12).

A deployment arm 136 connects the shelf 122 to the upper portion 118 tomaintain the shelf 122 in a generally horizontal configuration. Thedeployment arm 136 includes a first link 136A and a second link 136B. Afirst end of the first link 136A is pivotably attached to the shelf 122and a first end of the second link 136B is pivotably and slidablyattached to the upper portion 118 by a bracket 138. Second ends of thefirst and second link 136A, 136B are pivotably attached to each other.The bracket 138 includes a slot 140 for accepting a pin 142 located onthe first end of the link 136B. The slot 140 allows the pin 142 anddeployment arm 136 to move upward when the shelf 122 is moved in avertical plane into and out of the stowed position. Although only asingle deployment arm 136 and bracket 138 is shown, a second deploymentarm 136 and bracket 138 could be located on the opposite side of theshelf 122.

In accordance with the provisions of the patent statutes andjurisprudence, exemplary configurations described above are consideredto represent a preferred embodiment of the invention. However, it shouldbe noted that the invention can be practiced otherwise than asspecifically illustrated and described without departing from its spiritor scope.

What is claimed is:
 1. A method for operating lift assembly includingthe steps of: a) selectively connecting a first fork tine assembly to alift, wherein the first fork tine assembly includes a pair of first forktines connected to one another by a first cross-beam, the first forktine assembly further including a first push rod within each first forktine connected to a first wheel pivotably connected to the first forktine; b) lifting and moving at least one pallet with the first fork tineassembly; c) after said steps a) and b), removing the first fork tineassembly from the lift; d) after said step c), selectively connecting asecond fork tine assembly to the lift, wherein the second fork tineassembly includes a pair of second fork tines connected to one anotherby a second cross-beam, the second fork tine assembly further includinga second push rod within each second fork tine connected to a secondwheel pivotably connected to the second fork tine; and e) lifting andmoving at least one pallet with the second fork tine assembly.
 2. Themethod of claim 1 wherein the first fork tine assembly has a fork tineconfiguration that is different from the second fork tine assembly. 3.The method of claim 2 wherein the second fork tines are spaced furtherfrom one another than are the first fork tines.
 4. The method of claim 2wherein said step c) further includes disconnecting the first push rodsfrom the lift.
 5. The method of claim 4 wherein said step d) furtherincludes connecting the second push rods to the lift.
 6. A method foroperating lift assembly including the steps of: a) selectivelyconnecting a first fork tine assembly to a lift, wherein the first forktine assembly includes a pair of first fork tines connected to oneanother as a single unit, the first fork tine assembly further includinga first push rod within each first fork tine connected to a first wheelpivotably connected to the first fork tine; b) lifting and moving atleast one pallet with the first fork tine assembly; c) after said stepsa) and b), removing the first fork tine assembly from the lift; d) aftersaid step c), selectively connecting a second fork tine assembly to thelift, wherein the second fork tine assembly includes a pair of secondfork tines connected to one another as a single unit, the second forktine assembly further including a second push rod within each secondfork tine connected to a second wheel pivotably connected to the secondfork tine, wherein the first fork tine assembly has a fork tineconfiguration that is different from the second fork tine assembly; ande) lifting and moving at least one pallet with the second fork tineassembly.
 7. The method of claim 6 wherein the second fork tines arespaced further from one another than are the first fork tines.
 8. Themethod of claim 6 wherein said step c) further includes disconnectingthe first push rods from the lift.
 9. The method of claim 8 wherein saidstep d) further includes connecting the second push rods to the lift.